Botnets are one of the biggest threats to security systems and the digital world. The term is a combination of two words, robot and network. Now you can presume that a botnet is a network of robots. A network of robots used by cybercriminals to commit fraud and scams.
People behind botnets are called botmasters. The machines that have been compromised are known as zombies or bots. So we can say that a botnet is a zombie network. In fact, that’s a widely used name in cybersecurity.
How botnets work
For a botmaster, what matters is the size of the botnet network. The count is simple. The higher the number of infected devices or bots, the higher the attack’s force. And don’t think that in general it's something small. We're talking about hundreds, thousands and millions of zombie machines.
Take the criminal group 3ve as an example. It’s estimated that it has created a botnet network with about 1.7 million PCs in the world, causing losses of USD 29 million.
One of the reasons why botnets are so dangerous is because they can infect different types of devices, such as PCs, smartphones and smartwatches. If the device has Internet access, it’s a potential victim.
Botnets are used for different purposes, often involving financial gain. The most common aims are:
• DDoS attack (Distributed Denial-of-Service)
• Ad fraud
• Malware propagation
• Identity theft
• Spam dissemination
A botnet infection begins with a malware infection, caused by something as a Trojan, for example. Like most malware attacks, victims are required to open malicious emails, click on malicious files, malicious attachments or malicious URLs. It means that downloading software on a suspicious website may put the device at risk.
Botnets are also dangerous because of two other characteristics. The first is that many of them have the ability to self-propagate, just like a virus or a worm. The second is the camouflage capacity. Botnets are difficult to detect because their role is just to remain hidden.
How to prevent a botnet infection
Let's get right to the point: update your system, avoid suspicious emails, don’t click on suspicious links, don’t open suspicious attachments, avoid unknown downloads and sharing networks, and have an antivirus protection. If you’re thinking about your business security, evaluate a complete solution, such as a Secure Email Gateway, with anti-virus, anti-spam and sandbox.